Curve track system for toy vehicles

ABSTRACT

Curved elongated track sections including curved upper vehicle supporting face portions with spaced vehicle guiding flanges are described. The curved track sections are banked and have a successively changing radius of curvature for stablely changing the direction of travel of self-powered and freely rolling toy vehicles in a relatively small amount of space. Also described is a dual lane configuration and an added curve segment feature which provides additional vehicle direction change - from 180* to 197*, for example.

United States Patent [151 3,695,513 Baynes et al. 451 Oct, 3, 1972 CURVE TRACK SYSTEM FOR TOY 3,445,063 5/ 1969 Ferentiinos ..238/ l 0 F VEHICLES 3,206,122 9/1965 Frisbi'e et al ..238/l0 F [72] Inventors: William R. Baynes; Harvey w. 3,487,999 1/1970 Nash et al. ..238/l0 E g xgg Primary Examiner-.lames B. Marbert g n f g Assistant Examiner-Richard A. Bertsch asa a 0 1 Attorney-Seymour A. Scholnick [73] Assignee: Mattel, Inc., Hawthorne, Calif. [22] Filed: Oct. 1, 1970 2 ABS CT I d d urved elongated track sections inc u ing curve [2]] Appl' 77,159 upper vehicle supporting face portions with spaced vehicle guiding flanges are described. The curved 52 US. Cl. ..23s/10 E, 46/1, 46/43 sections are banked and have a successively 5 Field of Search 3 /19 30. 4 17 43. changing radius Of curvature f0! stablely changing the 238/10 10 1 6 direction of travel of self-powered and freely rolling toy vehicles in a relatively small amount of space. Also described is a dual lane configuration and an added [56] References Cited curve segment feature which provides additional vehi- UNITED STATES PATENTS cle direction change from 180 to 197, for example. 3,395,861 8/1968 Kindred ..238/10 F 17 Claims, 8 Drawing Figures 1 CURVE TRACK SYSTEM FOR TOY VEHICLES BACKGROUND OF THE INVENTION The background of the invention will beset forth in two parts.

FIELD OF THE INVENTION The present invention pertains to the field of toy vehicles and more particularly to a track system adapted to change the direction of travel of toy wheeled vehicles, both powered and unpowered and operating in a relatively wide speed range.

DESCRIPTION OF THE PRIOR ART Curve or direction changing accessories for track systems intended for use with toy vehicles having freely rotatable or rolling wheels are available in the prior art.

Such prior art curve accessories are generally used in conjunction with elongated sections of flexible plastic track which are joined together by tabs or track securing members fitted to the underside of the end portions of abutting sections of track. The curve accessories themselves generally include track engaging tabs to hold the flexible track in proper alignment and provide generally 90 and 180 change of vehicle direction along a curve having a constant radius of curvature. In some instances, the curve structure is banked to allow vehicles operating at relatively high speeds to successfully negotiate the curve and not leave the track.

It has been found that these constant radius curve accessories are generally adequate to handle gravity accelerated toy vehicles but are not as useful where the vehicles are given added acceleration by any of a number of presently available speed boosters because more gradual curves are required.

There is also now emerging an entirely new toy vehicle construction which utilizes a totally self contained electrical power plant which provides scale speeds of several hundreds of miles per hour. With this type of vehicle, the concept of constant radius curve structure has a particularly severe disadvantage in that a very large radius of curvature and a very high degree of bank angle is necessary to successfully handle this new breed of toy. The large radius of curvature necessitates the fabrication of a very large curve structure which generally cannot be tolerated in the home of prospective users, and the high bank angle, although required for the aforementioned high speed operation, will not allow a more slowly moving toy vehicle to traverse the curve without the danger of it falling from the track.

In contradistinction to the very well established custom and prejudice in the art to utilize constant radius curve accessories in order to cause a desired degree of change of vehicle direction, the present invention utilizes a curve track system wherein'a successively changing radius of curvature is employed. This new and novel system allows for the successful handling of wheeled toy vehicles operating over a wide range of speeds in a structure takingup considerably less area than a conventional track system providing the same change in vehicle direction.

SUMMARY OF THE INVENTION In view of the foregoing factors and conditions characteristic of prior art curve structures for wheeled 2 toy vehicles, it is a primary object of the present invention to provide a new and improved curve track system for miniature toy vehicles, not having the disadvantage of the prior art.

Another object of the present invention is to provide a curve track system which efficiently changes the direction of travel of toy vehicles moving at any of a wide range of velocities.

Still another object of the present invention is to provide a curve track system which occupies less area for a particular amount of vehicle direction change than was heretofore possible.

A further object of the present invention is to pro vide a curve track system which can easily be modified to increase or decrease the total change of direction negotiated by a wheeled toy vehicle.

Yet another object of the present invention is to provide a banked curve track system which is suitable for use with gravity accelerated and mechanically boosted free wheeling toy vehicles and also very high speed, completely self-contained electric powered vehicles.

According to the present invention, a curve track system for miniature toy vehicles having rolling wheels includes at least one curved elongated track section including a curved upper vehicle supporting face portion with vehicle guiding flanges projecting generally upwardly from each side of the face portion and extend ing generally substantially the entire length of the track section and spaced to permit lateral movement of the vehicles on the curved face portion. The curved track section is banked and has a successively changing radius of curvature.

The curve track system may be fabricated having a single, dual or multiple lane configuration and/or it may comprise one or more separate but complimenting and interlocking lengths of such curved track sections. For example, two relatively long curved track sections with equal but opposite curvature may provide a curve, while an additional relatively shorter curve segment may be inserted between the first mentioned sections to provide a converging arrangement useful for figure 8 layouts.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation together with further objects and advantages thereof, may best be understood by making reference to the following description, taken in connection with the accompanying drawings in which like reference characters refer to like elements in the several views.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a presently preferred embodiment of the invention wherein a relatively short curve segment is removably inserted between relatively longer curve sections to provide more than a 180 change of vehicle direction;

FIG. 2 is a perspective view of the curve segment and an adjoining curve section with the interconnecting portions exposed;

FIG. 3 is a partial view of two joined sections of curved track according to the invention;

FIG. 4 is an elevational view, partially broken away, taken along the line 4-4 of FIG. 3, which more clearly illustrates the interlocking track feature of the inventron;

FIG. 5 is a perspective view of a curved track section showing the two different types of interlocking configurations which may be incorporated;

FIG. 6 is a cross sectional view of an entrance or exit end of a curved track section taken along the line 6--6 in FIG. 5;

FIG. 7 is a cross sectional view taken along line 7-7 in FIG. 6 approximately midway along the length of the curved track section; and

FIG. 8 is a plan view of a 180 curve configuration wherein two curved track sections are joined together without an interdisposed curve sector.

DESCRIPTION OF THE PREFERRED EMBODIMENTS:

Referring to the drawings and more particularly to FIG. 1, there is shown a dual lane curve track system for miniature toy vehicles having rolling wheels, including first and second curved elongated track sections 11A and 118 having curved upper vehicle supporting face portions 13A and 138 with vehicle guiding flanges 15A and 15B projecting generally upwardly from each side of the face portions 13A and 13B, the center flange 15B being shared by both face portions. The flanges extend substantially the entire length of the track sections and are spaced sufficiently far apart to permit lateral movement of the vehicles on the curved face portions 13A and 13B.

Entrance/exit track interconnecting tabs 17A and 17B are provided at the ends 19A and 19B of the curved track sections having the greatest radius of curvature. These tabs generally follow the plane of the curved face portions 13A and 133, respectively, such that they are not parallel to the base surface nor do they maintain the exit angle (approximately 14) along their length. This configuration has been found to greatly improve the transition between the curve and conventional elongated flexible track, for example. While special interlocking structure 21 as best viewed in FIGS. 2-4 is provided to smoothly and reliably couple together portions of the curved track system according to the present invention, a more detailed description thereof to be set forth subsequently.

The complimentary curved track sections 11A and 118 may be fabricated from conventional synthetic materials using conventional molding techniques and may include lower skirt portions 23A and 233, each including trestle engaging socketsZSA and 25B disposed in the skirt portions. Also, the track interconnecting tabs 17A and 178 may either be molded as an integral part of the curved track sections (not shown) and into the open slot configuration of the aforementioned conventional elongated flexible track as described in US Pat. No. 3,489,999 which is assigned to the assignee of the present invention.

The aforementioned trestle engaging sockets 25A and 25B are adapted to receive an elevated bracket carried by trestle members and the like as fully described in a copending application, Ser. No.-

785,135, assigned to the assignee of the present invention. In this way, many configurations may be set up, such as for example, over and under type track systems and track systems having elevated portions.

Instead of fabricating the curve structure to provide a constant radius of curvature throughout the curve, the present invention-provides a successively changing radius of curvature as shown in detail in FIG. 1. As can be seen from this figure, a first segment of curved track 27 lies between lines 29 and 31 which intersect at a point X at an angle of approximately 24 and may have a radius of curvature of 23 inches, for example. A second segment 33, adjacent the first, lies between lines 31 and 35 and includes therebetween an angle of approximately 25 with a radius of curvature of 13 inches measured from the point Y. A third segment 37 of the curved track sections 11A and 1 1B is shown having an 8 inch radius of curvature as measured from a point Z and lies between lines 35 and 39 describing an angle of approximately 45. Of course, the curved track sections 11A and 113 have equal but opposite curvature as clearlyillustrated in the drawings.

In order to minimize skidding of a toy vehicle traversing the curved track system over a wide range of velocities, the vehicle supporting face portions are banked. The bank angle is less at the entrance/exit ends 19A and 19B of the track sections 11A and 11B (approximately l4) and increases to a maximum of approximately 55 at the opposite ends of these sections. In this regard, reference may be made to FIGS. 2, 5, 6 and 7 where an upstanding track support wall 51 with a surface footing 53 is clearly shown supporting the outer peripheral edge 55 of the track sections; the greater the walls vertical length, the greater will be the bank angle.

Between the two curved track sections 11A and 1 18 may be inserted a relatively short sector 61 having the same bank angle as that of the maximum curved ends 63A and 63B of the curved track sectoins to which it abuts. The sector 61 includes flanges 15 and face portions 13 conforming to and registering with the previously described flanges and surface portions of the longer track sections. Where such an additional sector of curved track is utilized, curved track system providing a 180 change of direction (90 per section) in possibly an oval layout may be extended to provide more than a l80 directional change to be used in constructing a figure 8 track pattern, for example.

As is the case where a smooth transition is exceedingly important between the road surface of the elongated flexible track sections abutting the entrance/exit ends 19 of the curved sections 11 as provided by the tabs 17, so must there be a smooth surface transition between the curved track sections. To insure this needed attribute, the special interlocking structure 21 is provided. It comprises generally an elongated slot 71 defined by an elongated flange or side member 73 held parallel to the plane of the surface portion 13 but below such surface by a distance equal to the track surface thickness and spaced from the end 63A of the curved section 11A and from an end 75 on the curve sector 61 by relatively short end members 77 and 79. It will be noted from the figures that the broad surface of the elongated member 73 lies in a plane making an angle with respect to a plane perpendicular to the face portion 13. Also, it can be seen from FIG. 2 that the end members 77 and 79 are set approximately parallel to the plane of the track support wall 51.

Specifically configured to slip into and hold onto the elongated slot 71 is an elongated tab structure 81 comprising an elongated depending tab member 83 equal in length to that of the slot 71 and extending downwardly from the end 638 of the curve track section 11B and from an end 85 on the curve sector 61. The broad surface of the tab member 83 lies in a plane conforming to the plane of the elongated slot 71 as defined by the side member 73 so that a tight fitting connection is provided when the depending member is inserted into the elongated slot. In this configuration, the abutting ends of the curved track are not only held tightly together but are held in a fixed relationship with the adjacent face portions in essentially perfect alignment for a very smoothrolling surface transition between the abutting track sections 11 and the track sector 61.

Furthermore, the matching lengths of the tab member 83 and the slot 71 provide for the alignment of the vehicle guiding flanges 15A and 15B. Additionally, stop tabs, not shown for the sake of clarity, may be provided to further aid in alignment of the curved sections. To further this end, a small detent rib 86 may be provided on the outer surface of the tab member 83 to force the abutting sections of track closer together and to act as a locking feature.

In order to strengthen the interlocking structure 21, transverse tapered gussets 87 and 89 are respectively positioned at several spaced points along the length of the tab 83 and along the inside surface of a depending end member 91 on the opposite side of the slot 71 from the member 73 (see FIG. 4). The tapered gussets 87 have a base width dimension equal to the width dimension of the slot 71 to assure tight abutting contact and the tapered ends of the gussets allows ease of assembly of the abutting members.

With reference to FIG. 8, a 180 curve system is shown utilizing the two cooperating 90 curved track sections 11A and 113. Here, the relatively short curve sector 61 is not inserted between the sections 11 that had added approximately 17 to the total change in direction of travel in the previously described configuration. These curved track sections may also have a successively changing radius of curvature that follow a parabolic relationship where a larger overall size is not of great concern. Alternately, each of the sections 11 may be divided into four or more segments having a successively changing radius of curvature instead of the three used in the system seen in FIG. 1. For example, with a successive radius plan where R, 8 inches; R 13 inches; R 22 inches; and R 47 inches, a total arc length of the curve will be approximately 24 inches and the curve layout size will be about X 19 inches. This compares to the first described three section plan in which R, was eliminated and the R radius length continued for the first 21 of the curve to yield a total curve layout size of about 10 X inches.

In order to reduce energy loss by the vehicles as they traverse the curve system, it is necessary to minimize the drag factor present when these vehicles come in contact with the guiding flanges 15. Accordingly, the flanges may have a sloping face portion 101 set at an angle preferably of about with respect to the normal to the face portion 13.

Although the curve track system herein described particularly referred to a dual lane arrangement, it should be understood that all the considerations discussed equally apply to a single lane system.

Furthermore, while a presently preferred embodiment of the invention has been described, it is clear that numerous modifications and other embodiments may be made within the skill of the ordinary engineer and without the exercise of inventive faculties.

What is claimed is:

1. A curve track system for miniature vehicles having rolling wheels, comprising:

at least one curved elongated track section including entrance and exit ends and a curved upper vehicle supporting face portion, and also including a vehicle guiding flange projecting generally upwardly from each side of said face portion and extending substantially the entire length of said track section and spaced to permit lateral movement of the vehicles on said curved face portion, said curved track section being banked and having a successively changing radius of curvature that is essentially the same and greatest at said ends.

2. A curve track system according to claim 1, including connector means at the ends of said track section for connecting said track section to additional track with a similar vehicle supporting face portion, the face portion of said track section and that of the additional track lying in a common plane.

3. A curve track system according to claim 1, wherein said track section includes means for providing said track section with a successively changing bank angle.

4. A curve track system according to claim 1, wherein the radius of curvature is the least in the area of the center of said curve track system.

S. A curve track system according to claim 4, wherein said bank angle is greatest when the radius of curvature is least.

6. A curve track system for miniature toy vehicles having rolling wheels, comprising:

a pair of elongated curved track sections each including entrance and exit ends and curved upper vehicle supporting face portions, and also including vehicle guiding flanges projecting generally upwardly from each side of said curved face portions and extending substantially the entire length of said curved track sections and spaced to permit lateral movement of the vehicles on said curved face portion, said curved track sections being banked and having successively changing radius of curvature that is essentially the same and greatest at said ends; and

connector means disposed adjacent said ends of said curved track sections for connecting said curved track sections with adjacent face portions lying in a common plane and for connecting said curved track sections to associated elongated track.

7. A curve track system according to claim 6, wherein said bank angle is greatest at the adjacentends of said curved track sections and least at their opposite ends.

8. A curve track system according to claim 6, wherein said radius of curvature is least at the adjacent ends of said curved track sections and greatest at their opposite ends.

a 9. A curve track system according to claim 6, wherein each of said curved track sections includes four consecutive curve sectors with successively decreasing radii of curvature and increasing bank angle.

10. A curve track system for miniature toy vehicles having rolling wheels, comprising:

at least one curved elongated track section including entrance and exit ends and a pair of adjacent and parallel curved upper vehicle supporting face portions, and also including vehicle guiding flanges projecting generally upwardly from opposite sides of said face portions and extending substantially the entire length of said track section, adjacent ones of said flanges being spaced to permit lateral movement of the vehicles on each of said curved face portions, said track section being banked and having a successively changing radius of curvature and bank angle, said radius of curvature being essentially the same and greatest at said ends.

11. A curve track system according to claim 10, including an additional curved track segment removably disposed between those ends of said curved track sections having the greatest bank angle and least radius of curvature, said curved track segment having the same bank angle and radius of curvature as at the ends of said curved track sections adjacent thereto.

12. A curve track system according to claim 11, wherein said curved track segment includes means for releasably connecting said curved track segment to associated ones of said curved track sections.

13. A curve track system according to claim 10, wherein the algebraic sum of the successively changing radii of curvature provides a 180 change in direction of vehicle travel.

14. A curve track system according to claim 10,

wherein the algebraic sum of the successively changing radii of curvature provides a change of direction of vehicle travel of over 15. A curve track system for use with elongated flexible track of the type having entrance and exit ends and an upper face portion adapted to support wheeled toy vehicles and guide flanges projecting generally upwardly from each side of said face portion to guide the vehicles and maintain them on the track, and further having a lower portion generally underlying said upper face portion, characterized by:

at least one elongated curve track section including a curved upper vehicle supporting face portion, vehicle guiding flanges projecting generally upwardly from each side of said curved face portion and extending substantially the entire length of said curved track section and spaced to permit lateral movement of the vehicles on said curved face portion, said curved track section being banked and having a successively changing radius of curvature and bank angle, said radius of curvature being essentially the same and greatest at said ends.

16. A curve track system according to claim 15, wherein said curved track section also includes a lower skirt portion wherein a trestle engaging socket is positioned.

17. A curve track system according to claim 16, wherein said lower skirt portion is disposed adjacent the inner curvature of said curved track section and wherein said trestle engaging socket lies approximately midway between the ends of said elongated curved track sections. 

1. A curve track system for miniature vehicles having rolling wheels, comprising: at least one curved elongated track section including entrance and exit ends and a curved upper vehicle supporting face portion, and also including a vehicle guiding flange projecting generally upwardly from each side of said face portion and extending substantially the entire length of said track section and spaced to permit lateral movement of the vehicles on said curved face portion, said curved track section being banked and having a successively changing radius of curvature that is essentially the same and greatest at said ends.
 2. A curve track system according to claim 1, including connector means at the ends of said track section for connecting said track section to additional track with a similar vehicle supporting face portion, the face portion of said track section and that of the additional track lying in a common plane.
 3. A curve track system according to claim 1, wherein said track section includes means for providing said track section with a successively changing bank angle.
 4. A curve track system according to claim 1, wherein the radius of curvature is the least in the area of the center of said curve track system.
 5. A curve track system according to claim 4, wherein said bank angle is greatest when the radius of curvature is least.
 6. A curve track system for miniature toy vehicles having rolling wheels, comprising: a pair of elongated curved track sections each including entrance and exit ends and curved upper vehicle Supporting face portions, and also including vehicle guiding flanges projecting generally upwardly from each side of said curved face portions and extending substantially the entire length of said curved track sections and spaced to permit lateral movement of the vehicles on said curved face portion, said curved track sections being banked and having successively changing radius of curvature that is essentially the same and greatest at said ends; and connector means disposed adjacent said ends of said curved track sections for connecting said curved track sections with adjacent face portions lying in a common plane and for connecting said curved track sections to associated elongated track.
 7. A curve track system according to claim 6, wherein said bank angle is greatest at the adjacent ends of said curved track sections and least at their opposite ends.
 8. A curve track system according to claim 6, wherein said radius of curvature is least at the adjacent ends of said curved track sections and greatest at their opposite ends.
 9. A curve track system according to claim 6, wherein each of said curved track sections includes four consecutive curve sectors with successively decreasing radii of curvature and increasing bank angle.
 10. A curve track system for miniature toy vehicles having rolling wheels, comprising: at least one curved elongated track section including entrance and exit ends and a pair of adjacent and parallel curved upper vehicle supporting face portions, and also including vehicle guiding flanges projecting generally upwardly from opposite sides of said face portions and extending substantially the entire length of said track section, adjacent ones of said flanges being spaced to permit lateral movement of the vehicles on each of said curved face portions, said track section being banked and having a successively changing radius of curvature and bank angle, said radius of curvature being essentially the same and greatest at said ends.
 11. A curve track system according to claim 10, including an additional curved track segment removably disposed between those ends of said curved track sections having the greatest bank angle and least radius of curvature, said curved track segment having the same bank angle and radius of curvature as at the ends of said curved track sections adjacent thereto.
 12. A curve track system according to claim 11, wherein said curved track segment includes means for releasably connecting said curved track segment to associated ones of said curved track sections.
 13. A curve track system according to claim 10, wherein the algebraic sum of the successively changing radii of curvature provides a 180* change in direction of vehicle travel.
 14. A curve track system according to claim 10, wherein the algebraic sum of the successively changing radii of curvature provides a change of direction of vehicle travel of over 180*.
 15. A curve track system for use with elongated flexible track of the type having entrance and exit ends and an upper face portion adapted to support wheeled toy vehicles and guide flanges projecting generally upwardly from each side of said face portion to guide the vehicles and maintain them on the track, and further having a lower portion generally underlying said upper face portion, characterized by: at least one elongated curve track section including a curved upper vehicle supporting face portion, vehicle guiding flanges projecting generally upwardly from each side of said curved face portion and extending substantially the entire length of said curved track section and spaced to permit lateral movement of the vehicles on said curved face portion, said curved track section being banked and having a successively changing radius of curvature and bank angle, said radius of curvature being essentially the same and greatest at said ends.
 16. A curve track system according to claim 15, wherein said curved track section also includes a lower skirt portion wheRein a trestle engaging socket is positioned.
 17. A curve track system according to claim 16, wherein said lower skirt portion is disposed adjacent the inner curvature of said curved track section and wherein said trestle engaging socket lies approximately midway between the ends of said elongated curved track sections. 